Friction bolster spring



A g-'30, 1938. D. F. sPRo'uL I 2,128,503

FRICTION BOLSI'ER SPRING Filed Aug; 28, 1955 2 sheets sheet l Z .Q 1 a 25 W I 26 25" B r45 i2 2 5 Jill anion 1902 3 07? D. F. SPROUL FRICTION BOLSTER SPRING Aug.- 30, 1938."

Filed Aug. 28, 1935 2 Sheets-Sheet 2 Patented Aug. 30, 1938 I v FRICTION BOLVSTER. SPRING Donald F. Sproul, Chicagoflllg' assignor to anwell-Westinghouse Company, a corporation of Delaware 1 Y Application August 28, 1935, Serial No. 38,259

9 Claims. (01. 267-9) This invention relates to bolster friction spring thus injuring or tending to injure the truck frame. :units, and one of the objects of the invention is Furthermore, with freely acting springs, harthe provision of a new and improved combined monic vibration of the springs is likely to occur, friction and spring unit that may be substituted as when the rail joints are imperfect and the for one or more of the springs of the convenspeed of the car is such that the engagement of tional spring assembly for railway cars. the wheels with the joint corresponds to the Another object of the invention is the provision natural spring vibration. The same result is of a new and improved spring unit having friclikely to occur where wheels having flat portions tion elements provided with horizontally arranged on their peripheries amused and the speed is helical springs. such that the flat portion of the wheel engages the 10 A further object of the invention is the prorail in timed relation to the natural spring vibravision of a new and improved friction spring unit tion. that has a high capacity and may be so positioned The present invention seeks to remedy these in the conventional spring assembly as to occupy difiiculties by the provision of a resilient unit hava minimum of space. ing friction means associated therewith for 15 Other and further objects and advantages of dampening the harmonic action of the springs the invention will appear from the following deand for assisting in'supporting the load. The scription taken in connection with the accomparts are so arranged that the friction between panying drawings, in which the parts is utilized for assisting the helical Fig. 1 is a side elevation of a portion of a railsprings in supporting the car body. Since the 20 way truck frame showing the invention in posifriction spring unit will prevent harmonic spring tion therein; action, the springs may be loaded greater than Fig. 2 is a plan view of a spring assembly show- One-half their travel, because they are not so ing the invention in position therein with parts likely 110- go Selid 011 Sudden Sheeks, and be broken away and parts omitted for the sak f they will not build up vibrations sufficient to cause 25 clearness; damage.

Fig. 3 is an end elevation of the friction spring Referring now to the drawings, the reference unit with parts in section; character I0 designates a side frame of a rail- Fig. 4 is a section on the line 44 of Fig. 3; way truck having a bolster opening II in which 5 is a perspective View of one of the the end of the bolster 12 extends, as is usual in thrust wedge members; such constructions. A spring plank [3 extends Fig 6 is a perspective ie of one of th into the opening II and rests on the spring seat friction wedge members; 7 I4 below said opening. A spring assembly l5 Fig. 7 is a side elevation with parts in section is insertedbetween the Spring plank and the of a modified form of construction; bolster for supporting the bolster from the side Fig. 8 is a vertical section on the line 88 of r m n the usual m nn Sin e the con- Fig.7; struction of the spring plank, bolster and side Fig. 9 is a section on the line 99 of Fig. 7; frame constitutes no part of the present invention, Fig. 10 is a perspective view of one of the thrust the Same being of e'eohventional well-knewn members; form of construction, it is not thought necessary 40 Fig. 11 is a perspective view of the other thrust o further illustrate des be the Same. member; and v The spring assembly I'5 comprises one or more Fig. 12 is a perspective view of one of the frichelical springs l6 a One e Of the Spring tion wedge members. friction units I7. The friction spring units I1 In modern railroading, the tendency is t i are' of such dimensions that each may be substicrease the weight of the load transported on each tuted f0r One more Of the helical Springs 6- car without increasing the weight of the car. the Conventional p fsp nest Or as- It was common practice until within recent sembly in Which fiVe helical Springs e used, the years to employ units of helical springs for supresilient friction units ll may be substituted for porting the car body from the car trucks. But, the Central Spring of the assembly- III the form 50 since the helical springs were free to expand and of construction shown, which is by way of exbe compressed, they could not be loaded to greater ample only, the unit I! has been substituted for than one-half their normal travel. Under any two of the helical springs l6. In order to balance greater load, the springs were likely to go soli'd the assembly, the unit I! is substituted for the 'when'they were subjected to unusual vibration, front springs at one end of the bolster and for the rear springs at the other end of the bolster. Each of the units IT, as disclosed in Figs. 1 to 5 inclusive, comprises an upper thrust member l8 and a lower thrust member Hi. The thrust member H3 is provided with a flat surface 2| for engaging a spring plate 22, and the lower thrust member 9 is provided with a similar flat surface 23 for engaging a spring plate 24, as is usual in such constructions. The upper thrust member I8 is provided with wedge faces 25 and 26, and the lower thrust member I9 is provided with corresponding wedge faces 21 and 28. The wedge faces of the thrust members are adapted to be engaged by the friction wedge members 29 and 3| which have wedge faces for frictionally engaging corresponding wedge faces of the thrust members.

A tension rod 32 extends horizontally through openings 33 in the friction wedge members and the ends thereof are provided with spring seats 34 and 35. Springs 36 and 31 are inserted between the friction wedge members and the spring seats 34 and 35, as clearly shown in Fig. 4 of the drawings. The friction wedge members may be provided with lugs 38 for engaging in the inner ends of the springs for positioning the same.

Suitable means are provided for limiting the expansion of the unit after compression. In the form of construction selected to illustrate one embodiment of the invention, each of the friction wedge members is provided with laterally extending lugs 39 and M at each end thereof for engaging inwardly extending flange members 42 and 33, respectively (see Fig. 3) on the thrust members l8 and 9. In order to provide clearance for the tension rod or bolt 32, the adjacent portions of the thrust members l8 and I9 are proyjded with concave recesses 44 (see Fig. 5).

The flange members 42 and 43 together with the connecting portions 40 and 50, respectively, constitute a column or abutment for limiting the compression of the unit and thereby preventing injury to the wedging mechanism and springs when the unit goes solid.

The capacity of the unit may be varied by adjusting the nuts 34 and 35 along the rod 32. In order to lighten the unit, the thrust members l8 and I9 may be hollow, as shown more particularly in Fig. 4.

In the operation of the device, when the unit is compressed by the movement of the car, the thrust member I8 is forced downwardly, thereby forcing outwardly the friction wedge members 29 and 3|. The springs 36 and 31 resiliently resist the outward movement of the wedges 29 and 3|, and the friction of the contacting wedge faces will tend to not only resist the compression of the unit, but will prevent harmonic spring action.

The form of the construction shown in Figs. 9 to 12, inclusive, differs from that just described principally in the means employed for limiting the expansion of the unit after compression. In this form of the construction, cooperating means are provided on the upper and lower thrust members forlimitingboththeexpansionandcompressionfor the-unit. The upper and lower thrust members 45 and 45 are provided with wedge faces which are adapted to be frictionally engaged by cooperating wedge faces of the friction wedge members 41 and 48 similar to that previously described.

One of the thrust members, as 45, is provided with depending skirts or flanges 49' having an offset portion 5| with an inwardly directing flange 52 at each side thereof which is adapted to engage beneath an outwardly extending flange 53 on the lower thrust member 45. When the parts expand, the flange 52 will engage beneath'the flange 53, thereby limiting the upward movement of the thrust member 45 or the separation of the thrust members. The offset portions 5| form shoulders or ledges 56 connected by plane surfaces 55 which are adapted to engage the corresponding flanges 53 and connecting portion 56 of the cooperating thrust member 46 for limiting the compression of the unit.

The depending skirt members cooperating with the side walls or extensions 5| of the lower thrust member 46 and the outer surfaces of the friction wedge members 41 and d8 constitute what may be termed a housing for the friction elements.

In use, the friction spring unit I! is positioned with the rod 32 extending transversely of the frame or longitudinally of the bolster, as shown in Figs. 1 and 2, although it may be arranged transversely of the bolster where suflicient space for the rod is available. The outer end of the rod 32 and the spring thereon as shown extend into or through the bolster opening in the side frame, see Figs. 1 and 2.

While the unit is shown as being applied to a spring assembly originally having four spiral springs, it is understood that this disclosure is by way of example only, and that the unit may be used with other forms of springs and in assemblies having more or less than this number of spirals or other springs without departing from the spirit of the invention, and it is understood that the invention as defined in the appended claims is not to be limited except by the prior art.

I claim as my invention:

1. In a bolster supporting spring assembly, a spring unit comprising a pair of vertically spaced thrust members, said members having adjacent wedge faces, a pair of horizontally arranged wedge elements having wedge portions engaging said faces, and skirt portions on the outer sides of one of said thrust members having flanges engaging cooperating flanges on the other thrust member for limiting the expansion of said unit.

2. In a bolster supporting spring assembly, a spring unit comprising a pair of vertically spaced thrust members, said members having adjacent wedge faces, a pair of horizontally arranged wedge elements having wedge portions engaging said faces, and cooperating faces and engaging flanges on said members and elements for limiting the vertical movements of said thrust members in both directions.

3. In a railway truck having a side frame provided with a bolster opening, a bolster in said opening, a spring assembly for supporting said bolster in said opening, said assembly comprising resilient means beneath said bolster, and a friction spring-unit associated with said resilient means for supporting said bolster from said frame, said unit comprising vertically arranged thrust members having wedge faces, wedge members at opposite sides of said thrust members engaging said faces, a rod extending through said wedge members transversely of said frame and extending outwardly into said opening, springs on the ends of said rod for resisting the separation of said wedge members upon the compression of said gear, and means including flanges on said thrust members for limiting the expansion of said gear.

4. In a spring unit for railway bolsters, a pair of follower members having wedging faces, laterally movable wedge members between said follower members for frictionally engaging said faces, means including helical springs compressible in planes at right angles to the movement of said wedge members for resisting the relative movement of said wedge members when said unit is compressed, means including interengaging elements integral with certain of said members for limiting the expansion of said unit, and means for varying the capacity of said unit.

5. In a bolster supporting spring assembly, a pair of vertically arranged thrust members having their adjacent faces converging to form wedge members, wedge elements on opposite sides of said thrust members engaging said faces, resilcal springs, a friction spring unit extending alongside said helical springs between said bolster and frame, said unit comprising movable and relatively stationary members and including upper and lower wedge members, laterally movable wedge elements engaging said last-named members, springs for resisting the outward movement of said elements when said unit is compressed, and interengaging means rigid with said first-named members for limiting the expansion of said unit.

'7. In combination, a truck frame having a bolster opening therein, a bolster in said opening, a spring assembly in said opening beneath said bolster, said assembly comprising apair of helical springs and a friction spring unit extending alongside said springs, said unit comprising a pair of vertically arranged thrust members having adjacent wedge faces, a pair of opposed wedge elements having Wedge faces engaging the wedge faces of said thrust members, a rod extending through said wedge elements transversely of said frame and extending outwardly into said openings, springs on the ends of said rod for resisting the separation of said wedge elements, means for varying the capacity of said assembly Without disturbing the relative positions of said helical springs, members and elements, and interengaging means integral with said wedge elements and thrust members for limiting the expansion of said unit.

8. In a bolster supporting spring assembly, a friction spring unit comprising a pair of opposed thrust members having adjacent wedge portions, a pair of wedge elements engaging said wedge portions, a rod extending horizontally through said wedge elements, springs on each end of said rod for resisting the outward movement of said elements, interengaging means on said members and elements and independent of said rod for limiting the separating movement of said thrust members, and means for varying the capacity of said unit.

9. In a. spring unit for railway bolsters, a pair of plates spaced apart vertically and movable toward and from each other, wedge mechanism between said plates, horizontally arranged coil springs for cooperating with said mechanism for resiliently resisting the compression of said unit, and interengaging flange members integral with said mechanism for limiting the expansion of said unit.

DONALD F. SPROUL. 

